Sit down because I'm jumping right into some science. This is for your husband to help understand why the bridge idea is not going to help you. Normal soil has an open pore structure that allows air and water to pass through it. Inside this structure lives 10s of thousands of species of beneficial microbes which thrive on the open pore structure. These microbes are Mother Nature's invention. As it turns out the species of microbes living in swampy land are different from those living in dryish land (lawns). When you allow standing water to stand for several days, that cuts off the air flow to the beneficial microbes and their populations begin to decrease. If this happens enough, normal grass will thin out and stop growing. They will be replaced by swamp grasses like nutgrass and some others. So it is important to keep the water from pooling on your lawn. Back to the issue... If your community has an ordinance that says homeowners must drain all water from their own property and not allow it to cross over onto a neighbor's land, then all you should have to do is call your city code compliance officers and make them deal with it. If you live in the savage west, then you might have to do it yourself. Talk to your neighbors and ask them to berm up their land at the fence to keep the water on their side. Since they already dug the ditch, they are unlikely to bend to your wishes. So when that doesn't work, berm up your side of the fence and push their water back onto their property (see how they like having standing pools of water!!). Six inches of berm would normally be plenty. Planting a lawn in the spring is not the best idea, but if you really have to you have to. If you can afford sod, then that should be better, but if you were planning to seed, I would not spend a lot on seed for a spring installation. What will happen is all that new grass will find itself competing with crabgrass which also sprouts in the spring. Your grass seed will be less hardy than the crabgrass and will thin out in the summer heat. It is not uncommon to have a full crabgrass lawn by July. It is much better to seed new grass in the fall because crabgrass seed is not sprouting then. It also gives the new grass all winter and spring to develop heat tolerant roots. Now a word on forum etiquette. This is not your thread. The original poster had a problem with soil structure. Your problem is neighborhood drainage. You should have opened a new topic so people who want to help you don't have to read through someone else's problem from last year - which is really not your problem. I also suspect you will need some advice on planting your lawn (spring? or fall - either one). Now is the time to ask, so post a new topic! When you ask about planting a new lawn, please mention specifically where you live. The zone system is not good for helping with lawns, so give a town or zip code. And if you want more help on the neighborhood drainage issue, I would still post a new topic with your new questions. This forum seems to have a lot of opinions about neighbors '-)

really hard to tell for sure but typically fungus in my area is reddish/yellow. You may have multiple problems. The problem with newbies is that they want to solve problems with chemicals (I was one of the worst offenders). The worst time to add fertilizer is when a grass is stressed and excessive nitrogen will show up as patterns matching the application method. If you just applied the nitrogen within the last few days you can reduce the effect by watering heavily for one day but if you applied it more than a few days ago you are probably past the danger period. Again, check the soil moisture at about 2-6" deep at several areas in your lawn each week. It should be slightly wet the day of watering and then let it go to slightly damp before watering again. Wet all the time just rots the roots and causes yellowing due to lack of nutrients. With most soils a twice weekly 1" watering in the summer is all you need. When the grass comes back on it's own (and I'm almost certain it will) then evaluate the soil like I said and take any corrective action required. Guessing and throwing chemicals at it will probably make things worse.

Thank you both. Fortunately the problem was solved fairly easily. We assumed the hood was source of the odor because when we pulled out the filters for cleaning, the awful smell seemed stronger in the hood than the surrounding room. But the next morning there was no odor in the hood. I can only guess that the dirty filters had accumulated some of the odor, and when they were out overnight any remaining smell in the hood and ductwork dissipated. We changed all of the filters (both VOC and HEPA) in the furnace/AC/aircleaner equipment and the smell hasn't returned. I'm still not sure what caused it. The filters weren't due to be changed for another month or more. I'm just very glad the stench is gone!

Premature posting. I wanted to add more to the above post before I submitted it. The "U" part of the trap is what holds water. If you look down the drain you might be able to see a portion of the pool of water that is held in the trap. The odor could also be hair and oil conglomeration that has been brewing in the waste pipe for a while. Hair from your head, oils from shampoos, conditioners, and soaps. I've snaked some waste pipes and had slugs of "stuff" several feet long come sliding out of the waste pipe. Ugh. On occasion I have seen vent pipes on the roof plugged up. Anything from bird nests to frost build up during cold weather. If the house is on a slab, an area about 18" square around the proposed drain location is normally boxed out. No concrete is poured in the boxed out area when the slab is poured. The drain pipe is piped into that box. Later the plumber can come in and set the trap in the boxed out area, then fill the boxed area as the shower pan is built. So...it could be a dry trap caused from lack of use/evaporation. That's the most common in a seldom used bath. It could be a blocked vent pipe. If your vent pipe is blocked, sometimes water sent down a drain in one part of the house can cause that same trap or a trap in another part of the house to siphon dry. An indication of that problem might show itself when you flush a toilet upstairs and see the water in a downstairs toilet bowl shimmer or bubble. Upstairs laundry can cause that as well. Siphoning can also be from the horizontal pipe extending off your shower's drain being too far from the vertical pipe that vents the shower. It could be a hair ball that's been smoldering on the pipes for a while. Do you get a good pull from your exhaust fan? When it's running, is there enough suction to hold a paper towel or a section of toilet paper up against the grill? Mongo